Stone sawing strand



June 8, 1937. G. G. GREENE STONE SWING-STRAND Filed May 3, 1.955

, strand Patented June s, v1937 UNITED STATES h 2,989,369 s'roNE sAwlNGSTRAND Guy Gilbert Greene, San

signor to The American Steel and 'pany oi'. New Jersey, a corporation ofJersey Francisco, Calif., as-v Wire Com- New Application May a, i935,serial No. 19,122

2 Claims. (Cl. 117-55) This invention relates in general tothe wire ropeart, and is particularly concerned with stone sawing strand, one of thevobjects being to effect an increase in the security of splicings in anymade of a plurality of intertwisted wires. A splicing in such a strandis commonly made by unraveling both ends to be joined for distancesthought to be sucient in view of the tension to be carried, theunraveled wires..then `being arranged so that alternatewires of one endare substituted 'for similarly laid Wires of the other end and viceversa. The wires areall closely iitted into place and their ends trimmedintor close abutting relationship and so that the the abutting ends ofthe others.

The resistance to slipping of-such splicing is dependent on thefrictional resistance of the valrious wires which must slide, and thetorsional resistance of the various wires to the torque set up by theirsliding through the helical paths resulting from their intertwistedrelationship. These yfactors are both variable, and slippage in splicingAis therefore all too common. Slippage is especially prevalent in stonesawing strand splicings because of the three-wire construction of suchstrand. l Now the present `invention covers a strand made of a pluralityof wiresthat are intertwisted with a lay of varied pitch. At the presenttime it is believed best that the lays should be of alternately shortand long pitch. This lay changes' in pitch at such spacing along thestrand as enables splicing to include at least one change in'pitch. Aspliced strand made in this manner should have a splicing wherein atleast one o f the abutting ends of the respective wires of which thestrand is made are oil- `s`et from the abutting ends of 'the others,this 40 resulting naturally from conventional splicing, and the lay ofthe strand will change in pitch at least once in this splicing. .Theresult of all this is vthat slippage of the splicing is retarded, due tothe fact that the Wires must follow helical paths of different pitchwhen they slip relative to each other so that the values of both.factors mentioned are increased.

Specic examples of the above are illustrated by the accompanyingdrawing, in which Figure 1 shows a stone sawing strand of thecharacterdescribed, with a conventional splicing that is unraveled so that it canbe studied; Figure 2 xshows the splicing in its assembled form; andFigure 3 shows a strand embodying theprinciples 1 55 described4 b'ut'reverseiy laid.

ly numbered I, 2 and then substituted for abuttingl ends of alternatewires are oiset from In the'drawing above described, the threeintertwisted wires may be respectively identified by the two diierentcross`hatchings and by the absence of such hatching. They arerespective- Figure 1 shows that the splicing in this strand is made byunraveling the three wires of the respective ends for considerabledistances, which in actual practice are ordinarily about ten feet inlength. The wire 2 of the right-hand end is the same wirein the lefthandend, while the wire lof the left-hand end is substituted for the samewire in the righthand end, the Wires 3 meeting in abutting relationshipat the center of the splicing. The increased resistance to slipping inthis splicing has already been explained. Also, as previouslsrexplained, `this results from the wires being intertwisted with a lay ofvaried pitch, the lines drawn. at 'right angles to the strand andrespectively marked S and L showing that the strand is'of alternatelyshort-and long pitch.

Figure 2 shows the splicing assembled, the lines marked S and Lindicating 'that the lay of the strand changes in pitch at least fourtimes at the splicing. This figure also shows that the abutting ends ofthe alternate wires are offset from the abutting ends of the others,this, however, simply 'resulting from the conventional splicing. l

Figure 3 is included for the purpose of showing that the principles ofthe invention may be applied lto reverse-lay stone sawing strand. It isobvious that it may also be applied to a leftlay stone sawing strand. l

Although a, stone sawing strand has been disclosed to provide a specificexample as required by the patent statutes, it should be' understoodthat the invention is applicable in general to the wire rope art, andthe scope of the following claims should not .be limited exactly to thisspecic example.

I claim: l

1. A pluralityV of Wires intertwisted to provide strand ends, alternateones of said wires of one of said ends being substituted for alternateones of the other to form a splicing, theends of said wires beingarranged in abutting relationshipv and so that -the abutting ends of atleast some of said: wires are oiset from the abutting ends -of others,said wires lbeing intertwisted in the same direction with a lay thatchanges in pitch at least at said splicing, whereby said wires musttravel through helical paths o f different pitches before said splicingcan be pulledapart.

' at least some Voi? said wires are oiiset from the others,said wiresbeing inter-twisted in the same direction at least at said splicing andhaving a lay that changes in pitch at least at said splicing, wherebysaid wires must travel through helical paths of different pitches beforesaid splicing can be pulled apart. i

GUY- GILBERT GREENE.

